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Re: [Phys-l] About the "why" and "how questins."



Robert Cohen wrote:
/snip/ "evolution on a small
scale" is a fact but "global evolution of species over the history of
the Earth" is not. Is there consensus on that?
The key words here seem to be global evolution and Earth history.

So it seems the contention concerns how universal in space is the observed
evolution of living forms , and how universal in time.

I recall that Newton asserted that what he could see as a local force which
gravitates masses, was to be applied at all times and all places.

This seems like a splendid idea - so that when metaphysicists find a need
to bend the rules (say of the limiting speed c) for just a moment of creation,
to make the cosmic lumpiness turn out right, I become quite uncomfortable.

And if I can easily demonstrate evolution in a quickly multiplying life form
within a week, I can expect much the same of slower breeding life forms
at any time and place.

I find it helpful to consider the species with very plastic genotypes, which
astound the eye with their variety in the scanty epoch of human selection.
Hereford, Jersey, Guernsey, Aberdeen Angus, Devon, Holstein, Ayrshire,
Beefalo, Brahman, Charolais, Hereford.
But a cow is much like any cow, with more or less of horns, udders, color.
A horse is recognizably a horse whether 30 inches at the shoulder - or six feet.
A cat has a tail, or not, long hair or not and various colors. But consider the dog.

The naked rat like animal beloved in Mexico, the tall deer hounds, the squat
pugnacious bull-dogs, the sausage dogs, the spaniels are disparate phenotypes
of their common genotype.

If this can be done in a thousand years or a few, what could reveal in a million years?
The zebra and the horse, perhaps. Or the tiger and lion. People call these
different species, yet they can still like dogs (with difficulty) interbreed.

The objections seem to spring more from religious than scientific precepts.

Brian W